Commit b815f196 authored Jan 21, 2011 by Paul Turner Committed by Ingo Molnar Jan 26, 2011

sched: Fix/remove redundant cfs_rq checks



Since updates are against an entity's queuing cfs_rq it's not possible to
enter update_cfs_{shares,load} with a NULL cfs_rq.  (Indeed, update_cfs_load
would crash prior to the check if we did anyway since we load is examined
during the initializers).

Also, in the update_cfs_load case there's no point
in maintaining averages for rq->cfs_rq since we don't perform shares
distribution at that level -- NULL check is replaced accordingly.

Thanks to Dan Carpenter for pointing out the deference before NULL check.

Signed-off-by: Paul Turner <pjt@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20110122044851.825284940@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent e37b6a7b

kernel/sched_fair.c

+1 −4

Original line number	Original line	Diff line number	Diff line
	@@ -722,7 +722,7 @@ static void update_cfs_load(struct cfs_rq *cfs_rq, int global_update)
	u64 now, delta;		u64 now, delta;
	unsigned long load = cfs_rq->load.weight;		unsigned long load = cfs_rq->load.weight;

	if (!cfs_rq)		if (cfs_rq->tg == &root_task_group)
	return;		return;

	now = rq_of(cfs_rq)->clock;		now = rq_of(cfs_rq)->clock;
	@@ -830,9 +830,6 @@ static void update_cfs_shares(struct cfs_rq *cfs_rq, long weight_delta)
	struct sched_entity *se;		struct sched_entity *se;
	long shares;		long shares;

	if (!cfs_rq)
	return;

	tg = cfs_rq->tg;		tg = cfs_rq->tg;
	se = tg->se[cpu_of(rq_of(cfs_rq))];		se = tg->se[cpu_of(rq_of(cfs_rq))];
	if (!se)		if (!se)